Bathymetric Analysis of Agulu Lake in Nigeria Using South Sde Acoustic Echo Sounder

Nzoiwu Chukwudi P.^{1, 2,} , Ozoemene Mmaduka L.¹, Ezeonyejiaku Chigozie D.¹, Igboanugo Chidera P.², Obikwelu Michael. C.¹ and Igboanugo Ifunanya R.¹

¹Department of Geography and Meteorology, Nnamdi Azikiwe University, Awka, Nigeria

²National Water Resources Capacity Building Network and Climate Change Centre, Nnamdi Azikiwe University, Awka, Nigeria

Cite this paper:
Nzoiwu Chukwudi P., Ozoemene Mmaduka L., Ezeonyejiaku Chigozie D., Igboanugo Chidera P., Obikwelu Michael. C. and Igboanugo Ifunanya R.. Bathymetric Analysis of Agulu Lake in Nigeria Using South Sde Acoustic Echo Sounder. American Journal of Water Resources. 2025; 13(3):97-103. doi: 10.12691/ajwr-13-3-4

Abstract

This paper focuses on the bathymetric analysis of Agulu Lake to assess the water resources potential of the lake. The bathymetric map of the lake was developed for the first time at an interval of 0.5m based on depth measurements at 113 points. The maximum recorded depth is 9.5m, a shoreline length of 6.43km, and a lake volume of 4.7 × 10^6 m^3. The empirical equation for predicting lake depths, area, and volume was established. The surface area of the lake, obtained from satellite imagery, was used to predict lake depths. We evaluated the performance of these empirical relationships using Nash-Sutcliffe efficiency. The results showed that the lake depth and area are well correlated (r2 = 0.94) while the performance of the regression model developed yielded a Nash–Sutcliffe Efficiency (NSE) of 0.95. The relationship between the lake area and depth characteristics of Agulu Lake is statistically significant. Similarly, the relationship between the volume and the lake's depth showed a correlation of r2 = 0.99. The findings obtained in this study are crucial for informed decision-making by stakeholders in the water sector, the Ministry of Tourism, and local communities in managing water abstractions from Agulu Lake, as well as for developing the Lake as a tourist site.

Keywords:
Bathymetry Agulu Lake echo sounder lake depth lake volume

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